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<BODY><H2><a href="../contents.htm">Tcl8.6.11/Tk8.6.11 Documentation</a> <small>&gt;</small> <a href="contents.htm">Tcl Commands</a> <small>&gt;</small> append</H2>
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<H3><A NAME="M2">NAME</A></H3>
append &mdash; Append to variable
<H3><A NAME="M3">SYNOPSIS</A></H3>
<B>append </B><I>varName </I>?<I>value value value ...</I>?<BR>
<H3><A NAME="M4">DESCRIPTION</A></H3>
Append all of the <I>value</I> arguments to the current value
of variable <I>varName</I>.  If <I>varName</I> does not exist,
it is given a value equal to the concatenation of all the
<I>value</I> arguments.
The result of this command is the new value stored in variable
<I>varName</I>.
This command provides an efficient way to build up long
variables incrementally.
For example,
&ldquo;<B>append a $b</B>&rdquo;
is much more efficient than
&ldquo;<B>set a $a$b</B>&rdquo;
if <B>$a</B> is long.
<H3><A NAME="M5">EXAMPLE</A></H3>
Building a string of comma-separated numbers piecemeal using a loop.
<P>
<PRE>set var 0
for {set i 1} {$i&lt;=10} {incr i} {
    <B>append</B> var &quot;,&quot; $i
}
puts $var
# Prints 0,1,2,3,4,5,6,7,8,9,10</PRE>
<H3><A NAME="M6">SEE ALSO</A></H3>
<B><A HREF="../TclCmd/concat.htm">concat</A></B>, <B><A HREF="../TclCmd/lappend.htm">lappend</A></B>
<H3><A NAME="M7">KEYWORDS</A></H3>
<A href="../Keywords/A.htm#append">append</A>, <A href="../Keywords/V.htm#variable">variable</A>
<div class="copy">Copyright &copy; 1993 The Regents of the University of California.
<BR>Copyright &copy; 1994-1996 Sun Microsystems, Inc.
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